Method of and apparatus for carbonization or destructive distillation



Jan. 15 @1924. HAM-9M] s. MCEWEN METHOD OF AND APPARATUS FOR CARBONIZATION OR DES'I RUCTIVE 'DI'STI [LLATION Filed June 16. 1920 s Sheeizs-Sheet &

S. M EWEN METHOD OF AND APPARATUS FOR CARBONIZATION OR DESTRUCTIVE DISTILLATION Filed June .16, 1920 s Sheets-Sheet 2 SAMUEL MCEWEN, OF LONDON, ENGLAND.

METHOD OF AND APPARATUS FOR CARBONIZATION 0R DESTRUCTI Application filed June 16, 1920. Serial No. 389,399.

To all whom it may concern:

Be it known that I. SAMUEL MCEWEN. a subject of the King of Great Britain, residing in London, En land, have invented a certain new and use ul Improved Method of and Apparatus for Carbonization or Destructive Distillation. of which the following is a specification.

Attempts which have hitherto been made to carbonise finely divided fuel so as to obtain a comparably subdivided coke have consisted in showering the powdered fuel through a retort externally heated so that the supply of heat is maintained within the retort by transference from the walls of the retort. Such methods are not economical and the capacity of the retorts used is limited by the area of the hot surface required to maintain the contents of the retort at the necessary temperature.

By the present invention the powdered fuel is heated while in suspension in an elastic fluid' which is caused to travel to delay the settling of the particles by gravitation and which is maintained at the necessary temperature by heat supplied within the walls of the zone of carbonization.

The elastic fluid may be heated before introduction into the carbonising chamber or may be products of combustion of gases introduced into the chamber. In the former case the gases produced by the carbonization may be the elastic fluid, and in either case the elastic fluid may be circulated through the ca-rbonising chamber, due provision being made for separating the carbonised fuel at a suitable point.

The time during which a particle of fuel should be subject to the temperature of car bonization depends on its size. Since strictly uniform grinding is impracticable provision is preferably made for suspension of the coarse particles for a longer period in the heated elastic fluid, than of the finer particles. Thus the gas carrying the particles may be caused to travel upwards in an expandin chamber so that the coarse parti-- cles may bedelayed by gravity more thanthe fine particles. Such a provision is also useful for securing a relative movement of the elastic fluid and the particles which it carries, .a result obtainable in several other ways, such as by baflies in the-path of the fluld.

The accompanying diagrams illustrate the invention when circulation is applied The parts marked with the same reference letters in the three figures perform the same function.

Fig. 1 is a diagrammatic elevation of a form of apparatus in which the volatile products of the carbonization are circulated by means of a fan;

Fig. 2 is a like View of an apparatus in which the circulation is by means of products of combustion issuing through an injector; and

Fig. 3 is a vertical section of an apparatus in which the subdivided fuel' is blown into the carbonising chamber.

Referring to Fig. 1 coal dust from a hopper a is discharged by a gas-tight feeding device 6 into a pipe 0 where it enters a current of gas circulated through the system by a fan d in the direction indicated by the arrows.

Between the fan d and the coal feed I) the pipe 0 receives the products of combustion from the furnace f fed through a pipe f with some of the gas produced, and through pipe f with air in such proportion that the mixture of gas and air contains the minimum excess'of oxygen above that required to burn the gas. The delivery pipe of the fan (1 extends through the upper part of the furnace f so that some of the heat of the, products of combustion is used in heating the gas in circulation before it enters the system.

The hot gas having taken up the coal dust carries it in suspension into an upwardly expanding pipe or chamber h where the effect already referred to is obtained. Having passed up the expanding chamber the dust and gas descend to enter tangentially into the upper part of a separator 11 constructed like the apparatus commonly known as a cyclone. Here the now carbonised dust collects to be removed by periodically opening the discharge valve it. while the gas is discharged along the axis of the separator through the pipe Z which conducts it intoz the suction side of the fan d through lpe The volatile products from the coal dust escape through the counter-weighted relief valve 0 into a pipe p which conducts them to a-condenser q, where oils and the {like are condensed while the permanent gasespass by pipe 'r to a gas holder (not shownfa portion bei pg drawn into the furnace f.

apparatus may be charged at the bethrough an injector pipe to at a velocity suflicient to maintain the circulation by withdrawing the gas from the separator, i, through pipe t.

Fig. 3 shows a modification in which the fuel is blown into a vertical carbonisingchamber heated by hurning gas.

The chamber c is surrounded at its upper part Witlran annular pipe 6 supplied with powdered coal from a hopper Jets b form communication between the pipe I) and the interior of the chamber 0. Into the lower part of the chamber extend gas burners f. I At the top of the retort a pipe p con ducts the volatile products of combustion and the products of combustion from burners f through a condensing plant (not shown); a portion of the gases from this plant are returned by blower dto the annular ipe b to carry the powdered coal through jets 6 into the chamber 0.

Here the particles of coal descend meeting the hot products of combustion rising from the burners f which are fed with another portion of the gases from the condensing plant.

Having thus described the nature of the said invention and the best means I know for carryingthesame into practical effect, I claim 1. A process of carbonisingfinely subdivided fuel consisting in suspending the finely sub-divided fuel in a gas at a tempera-' ture necessary for carbonization of the fuel, which process consists 1n removing a portion of the gases from the carbonising chamber, burning the said portion in close proximity to the zone of carbonization, introducing the hot products of combustion into the said zone so that they travel therein in such manner as to delay the settling of the particles by gravitation, and collecting in finely subdivided state the carbonised fuel thus produced.

2. 'A process of carbonising finely subdivided fuel consisting in suspending the finely sub-divided fuel in a gas at a temperature necessary for carbonization of the fuel. which process consists .in removing a portion of the gases from the carbonising chamber, burning the said portion within the walls of the carbonising zone so that the products of combustion travel in the said zone in such manner as to delay the settling of the particles by gravitation, and collecting in finely subdivided state the carbonised fuel thus produced.

ducing the hot products of combustion into the said zone, so that they travel in such manner as to delay the settling of the particles by gravitation and then separating the carbonised' fuel thus produced from the travelling products in finely subdivided state and causing the said products tocontinue to travel in a closed circuit to receive fresh fuel, the condensible products of carbonization being removed from the apparatus.

4. A- process of carbonising finely subdivided fuel consisting in suspending the finely sub-divided fuel in a gas at a temperature necessary for carbonization of the fuel, which process consists in removing a portion of the gases from the carbonising chamber, burning the said portion in close proximity tothe zone .of carbonization, introducing the hot products of combustion into the said zone so that they travel in such manner as to delay the settling of the par-. ticles by gravitation and, in a portion of their course, in an upward direction with diminishing velocity, then separating the carbonised fuel thus produced from the travelling products in finely subdivided state and causingv the said products to continue to travel in a closed circuit to receive fresh fuel, the co-ndensible products of carbonizetion being removed from the apparatus. 5. A process of carbonising finely subdivided fuel consisting in suspending the finely sub-divided fuel in a gas at a temperature necessary for carbonization of the fuel, which process consists in removing a portion of the gases from the carbonising chamber, burning the said portion in close proximity to the zone of carbonization, introducing the hot products of combustion into the said zone so that they travel in such manner as to delay the settling of the particles by gravitation and in such a manner that there is reactive movement between the' particles and the gases, and then separating the carbonised fuel thus produced from the travelling products in finely subdivided state and causing the said products to continue to travel in a closed circuit to receive fresh fuel, the condensible products of carbonization being removed from the apparatus.

In testimony whereof I have signed my name to this specification. 

